Harper's New Monthly Magazine, Volume 1, No. 4, September, 1850

by Various

While passing through this dense cloud, the voyagers carefully observed the barometer, and knew by the rapid fall of the mercury that they were ascending with a great velocity. Fifteen minutes elapsed before they emerged from the cloud; when they did so, however, a glorious spectacle presented itself. The balloon, emerging from the superior surface of the cloud, rose under a splendid canopy of azure, and shone with the rays of a brilliant sun. The cloud which they had just passed, was soon seen several thousand feet below them. From the observations taken with the barometer and thermometer, it was afterward found that the thickness of the cloud through which they had passed, was 9800 feet—a little less than two miles. On emerging from the cloud, our observers examined the barometer, and found that the mercury had fallen to the height of 18 inches; the thermometer showed a temperature of 45° Fahr. The height of the balloon above the level of the sea was then 14,200 feet. At the moment of emerging from the cloud, M. Barral made polariscopic observation, which established a fact foreseen by M. Arago, that the light reflected from the surface of the clouds, was unpolarized light.

The continued and somewhat considerable fall of the barometer informed the observers that their ascent still continued to be rapid. The rain which had previously fallen, and which wetted the balloon, and saturated the cordage forming the net-work, had now ceased, or, to speak more correctly, the balloon had passed above the region in which the rain prevailed. The strong action of the sun, and almost complete dryness of the air in which the vast machine now floated, caused the evaporation of the moisture which enveloped it. The cordage and the balloon becoming dry, and thus relieved of a certain weight of liquid, was affected as though a quantity of ballast had been thrown out, and it darted upward with increased velocity.

It was within one minute of eleven, when the observers finding the barometer cease the upward motion, and finding that the machine oscillated round a position of equilibrium by noticing the bearing of the sun, they found the epoch favorable for another series of observations. The barometer there indicated that the balloon had attained the enormous height of 19,700 feet. The moisture which had invested the thermometer had frozen upon it, and obstructed, for the moment, observations with it. It was while M. Barral was occupied in wiping the icicles from it, that, turning his eye upward, he beheld what would have been sufficient to have made the stoutest heart quail with fear.

To explain the catastrophe which at this moment, and at nearly 20,000 feet above the surface of the earth, and about a mile above the highest strata of the clouds, menaced the voyagers, we must recur to what we have already stated in reference to the balloon and the net-work. As it was intended to ascend to an unusual altitude, it was of course known, that in consequence of the highly rarefied state of the atmosphere, and its very much diminished pressure, the gas contained in the balloon would have a great tendency to distend, and, consequently, space must be allowed for the play of this effect. The balloon, therefore, at starting, was not nearly filled with gas, and yet, as we have explained it, very nearly filled the net-work which inclosed it. Is it not strange that some among the scientific men present did not foresee, that when it would ascend into a highly rarefied atmosphere, it would necessarily distend itself to such a magnitude, that the netting would be utterly insufficient to contain it? Such effect, so strangely unforeseen, now disclosed itself practically realized to the astonished and terrified eyes of M. Barral.

The balloon, in fact, had so swelled as not only completely to fill the netting which covered it, but to force its way, in a frightful manner, through the hoop under it, from which the car, and the voyagers were suspended.

In short, the inflated silk protruding downward through the hoop, now nearly touched the heads of the voyagers. In this emergency the remedy was sufficiently obvious.

The valve must be opened, and the balloon breathed, so as to relieve it from the over-inflation. Now, it is well known, that the valve in this machine is placed in a sort of sleeve, of a length more or less considerable, connected with the lower part of the balloon, through which sleeve the string-of the valve passes. M. Barral, on looking for this sleeve, found that it had disappeared. Further search showed that the balloon being awkwardly and improperly placed in the inclosing net-work, the valve-sleeve, instead of hanging clear of the hoop, had been gathered up in the net-work above the hoop; so that, to reach it, it would have been necessary to have forced a passage between the inflated silk and the hoop.

Now, here it must be observed, that such an incident could never have happened to the most commonly-practiced balloon exhibitor, whose first measure, before leaving the ground, would be to secure access to, and the play of the valve. This, however, was, in the present case, fatally overlooked. It was, in fine, now quite apparent, that either of two effects must speedily ensue—viz.: either the car and the voyagers would be buried in the inflated silk which was descending upon them, and thus they would he suffocated, or that the force of distention must burst the balloon. If a rupture were to take place in that part immediately over the car, then the voyagers would be suffocated by an atmosphere of hydrogen; if it should take place at a superior part, then the balloon, rapidly discharged of its gas, would be precipitated to the earth, and the destruction of its occupants rendered inevitable.

Under these circumstances the voyagers did not lose their presence of mind, but calmly considered their situation, and promptly decided upon the course to be adopted. M. Barral climbed up the side of the car, and the net-work suspending it, and forced his way through the hoop, so as to catch hold of the valve-sleeve. In this operation, however, he was obliged to exercise a force which produced a rent in a part of the silk below the hoop, and immediately over the car. In a moment the hydrogen gas issued with terrible force from the balloon, and the voyagers found themselves involved in an atmosphere of it.

Respiration became impossible, and they were nearly suffocated. A glance at the barometer, however, showed them that they were falling to the ground with the most fearful rapidity.